the best way to start is something small.
design a hat.
YOU can just knit a simple beanie hat.. but
use an interesting stitch
but better is to knit a hat-
make it an interesting shape, or technique
MOST HATS are top down or bottom up.
Some are cross wise
but how else can a hat be shaped?
(and what shape do you want for your hat?)
there are pork pie, and pill box and folded hats.. there are hats with ear flaps, and shaped hats (EZ did some very interesting shapes with hats.. Anne Zilboorg did even more interesting shapes.--if you can see her book (its out of print and resells for $200 to $400--and yes, it is that good a book!)look at it.. (try googling her name and see if you can find images from others who have knit her designs)
I Have done some interesting shapes. Look at those hats, and others, and out do us.(go to my blog ,and look at my photogallery of hats.. sure i have some beanies.. but i also have other interesting shapes and designs--)
Or do the same for a scarf pattern--Have you seen the book Knitting New Scarves? Very different scarves.. some super easy, some not-- but all very different than the standard flat scarves (with stripes or other minor modifications to plain knitting..
On ravelry there is a knitter who LOOKED at a knotted band design (celtic knot) and knit a mitered band (about 2 inches wide, in simple double knit) and then knotted it.. the miters made the band stay perfectly flat.. (and since it was knotted, she needed 3 times the lenght of knitting..)(see geek knitters group)
Not something i am interested in doing.. but..
There are plenty of idea to explore.
when you move on to garments, Look for Debbie Newton's book on Designing Knitwear.. (its still available.. i saw it recently in a chain store.. discounted) but even at full price its worth it (about $30)
Personally, i don't much like it.. (too many cables and seamed garments--NO yokes (circle/semi circle) --but it does have some good info.
The Big Book of Knitting (Katerina Buss) is an other good resourse, too, (again, still in print, both hard cover and paperback, about $25)